Without those challenging backgrounds having made them who they are they may have never achieved greatness if they had everything given to them the same as other children.
That's one way of looking at it. Another way of looking it is to wonder just how many kids will never achieve greatness because they didn't get everything given to them same as other children?
Look at the most successful athletes in any given sport. How many them actually come from deprived backgrounds as opposed to the number that got all the coaching and equipment and nutrition and time off from school/work they needed?
Just because suffering can breed excellence doesn't mean it will -- and it sure as hell shouldn't have to.
You may want to look at some of Robert Coles books and findings in which children that come from a poor socio-economic status often find hope and happiness in their lives and are much more adept at over-coming struggles than middle-class and above children who become bored and often have an entitled attitude towards life. Tribulations often build character and help children to become better problem solvers. The most successful athletes(read here Champions) 9/10 times are from poor socio-economic backgrounds...the NFL is littered with them.
That may well be. However. That is hardly an argument in favour of the suffering and difficulty that comes with being from those backgrounds. Even those champions would have been helped by something like @sportspodium, had it been available.
Maybe there'd have been more champions.